Concatenate Fields in Rule Editor

[yguo]

I am trying to concatenate two form fields values into one. In the rule editor, I tried to Concat a string with a field value. It didn't throw errors, but it just won't work. 

guideBridge.resolveNode("from-hidden").value = Concat("ABC", this.value);

I don't find Concat under Functions from the side panel. Is that why it's not working? How do I make it work?

[Pulkit_Jain_ · Accepted solution]

@yguo 

Use the code editor instead and add the below js to any event:

var text1 = "ABC";
Field2.value = text1.concat(Field1.value);

 Example: I added this js to the button click event and prefilled the next field.